Pneumatic drill.



J. C. H. VAUGHT.

PNEUMATIC DRILL.

APPLICATION FILED OCT. 23. 1915.

Patented. Apr. 17, 1917.

2 SHEETS-SHEET l.

6* f' as 1.. C. H. VAUGHT.

PNEUMATIC DRILL.

APPLICATION FILED 00123. I915.

Patented Apr. 17, 1917.

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attozmaiy STATE @FFKQE.

JAMES C. H. VAUGI-IT, OF NEW YORK, N. Y.

PNEUMATIC DRILL.

Application filed October 23, 1915.

To all whom it may concern:

Be it known that 1, JAMES C. H. VAUGI-IT, a citizen of the United States, residing at New York, in the county and State of New York, have made a certain new and useful Invention in Pneumatic Drills, of which the following is a specification.

This invention relates to pneumatic hammer drills.

The object of the invention is to provide a pneumatic hammer drill which is simple in structure, and eflicient in operation.

A further object of the invention is to pro vide a feed apparatus for a drill of the class described which is double acting.

A further object of the invention is to provide means which are simple and efficient for securing double action of drill feeding apparatus which employs for the operation thereof the same pressure medium that opcrates the hammer.

A further object of the invention is to provide simple and eflicient controlling means for the double action of the drill feeding apparatus. I

Further objects of the invention will ap pear more fully hereinafter.

The inventionconsists in the construction, combination, location, and relative arrangement of parts, all as will be more fully hereinafter set forth, as shown in the accompanying drawings. and finally pointed out in the appended claims.

Referring to the drawings,

Figure 1 is a view in side elevation, of a drill embodying my invention, the drill being at the limit of its forward position.

Fig. 2 is a similar view partly sectional, with the drill shown at the limit of its re tracted position.

Fig. 3 is a sectional view taken on the line 3, 3, Fig. 2, and looking in the direction of the arrows.

Fig. 4 is an enlarged detail view partly sectional, showing the pressure supply connection and embodying my invention.

Fig. 5 is a view in longitudinal section of the double acting feed mechanism employed in connection with my invention.

Fig. 6 is an enlarged detail view in section showing the controlling means of the double acting air feed mechanism.

Fig. 7 is a sectional view taken on the line 7, 7, Fig. 6, and looking in the direction of the arrows.

Fig. 8 is a sectional view taken on the line Specification of Letters Patent.

Patented Apr. it, 191?.

Serial No. 57,585.

8, S, Fig. 6, and looking in the direction of the arrows.

9 is a view similar to Fig. 7, showing a reversal of the ports.

The same part is designated by the same reference numeral wherever it occurs throughout the several views.

In hammer drills, and particularly those designed for drilling rock or the like, it is the usual custom to employ a pneumatically operated hammer, said hammer being operatcd with fluid pressure from a suitable source, and controlled by a valve. The fluid pressure actuates the hammer causing the same to deliver its working stroke very rapidly upon the end of the drill bit. It is essential however to provide means to advance the working parts of the machine as the work progresses. Heretofore this has been accomplished by a suitable feed screw and connections operated by hand, for feeding the machine and drill bit forwardly as the work progresses, and by reversing the hand operated screw feed mechanism the machine and drill bit are retracted to initial position.

The disadvantages of the arrangement heretofore used, are obvious and many. In the first place, the feed mechanism being operated by hand cannot be maintained uni.- form and. constant. A gain, the attention of the operator is constantly required at all times to operate the feed screw and to attend to other duties connected with the operation of the machine. A further and a very important disadvantage is that when the limit of forward travel of the drilling machine is reached great loss of time is caused in returning the same to its initial position, this operation being accomplished by means of the hand operated feed screw.

it is among the special purposes of my present invention to provide a drilling machine and a feed mechanism therefor which will overcome all of the above enumerated and other objections and disadvantages, and which will insure steady uniform feed of the drilling machine, without the attention of the operator, and which is double acting in operation.

In the drawings, 1 show one embodiment of my invention wherein 1 designates generally a working cylinder in which the pneumatic hammer operates in the well known manner, and the details of which do not form a part of my present invention except as will be more fully hereinafter pointed out. Mounted on the casing of the machine 1, is the usual valve chest 2 provided with a suitable connection 3 to a source of fluid pressure, not shown, and an exhaust opening 4, and a suitable valve control therefor as, for instance, the handle 5. In accordance with my invention I employ a feed tube or cylinder 6 secured to the drilling machine 1 in any desired or suitable manner. I show a simple and eflicient means for accomplishing this result, but to which my invention, in its broad scope, is not to be limited or restricted, wherein I provide the usual head 7, of the drilling machine with a downwardly projecting lug 8, adapted to fit into a vertical slot cut into the end of the feed cylinder and drive a pin 9 there through. The body of the drilling machine may be secured to the outer surface of the feed cylinder 6, if desired, in any suitable manner. The cylinder 6 may be closed at one or both ends, as shown, the slit portion thereof to receive the lug 8 of the head 7 of the drilling machine 1, forms a portion of a. plug, preferably a screw plug indicated at 10, to close one end of the cylinder while the other end of the cylinder is closed in any suitable manner to insure air tightness. For this purpose, I show a screw plug 11 provided with a suitable seat to receive a washer, such as a leather washer 12, which is held in place by screw plug 13. It will be understood, however, that these are all details to which my invention, in its broad scope, is not to be limited or restricted.

Within the feed cylinder 6 is a piston rod 11-, provided with a head 15, to fit snugly against the interior wall of the cylinder. The usual cradle or shell 16 is shown and is provided with channels 17 adapted to form guides for the movement of the drilling machine therein. Stay rods 18 are suitably secured to the shell or cradle 16 on opposite sides thereof, as by brackets cast thereon and nuts 19. The stay or brace rods 18 are secured to each other at their free ends by means of a head 20, to which is also secured, for example, by means of a bolt head or nut 22, the piston rod 14c.

Thus it will be seen that the piston rod and head are stationary with respect to the shell or cradle, but upon admission of pressure to either side of the piston head 15, the feed cylinder 6 will move relatively to the piston head until the plug at the other end of the cylinder brings up against the piston head. To allow the pressure to flow to either side of the piston head within the cylinder, I provide ducts 23, 2 1*, with openings into the feed cylinder at the respective remote ends thereof. These ducts or channels may be formed in any suitable manner, as, for example, by brazing or welding a tube or 3 channel trough upon the outer surface of the feed cylinder 6, as shown in Figs. 3 and 5. My invention, however, in its broad scope as defined in the claims, is not to be limited or restricted to the form of construction shown and described. The important feature in this regard is the location of the ducts or passages 23, 24 exteriorly of the cylinder where they do not prescribe or limit the pressure area of or the effective application of the pressure to the piston within the cylinder. In accordance with my invention, I braze, weld, or otherwise secure to the feed cylinder 6, a valve chest 24:, provided with an inlet orifice 25, and two ports 26, 27 in register, respectively, with the ducts or passages 23, 24, and an outlet orifice 28, as shown in Fig. 6. A two-way valve of any suitable or desired construction, shown at 29, controllable by any suitable means, such as by a handle 30, operates in the valve chest and is held therein by a nut or bolt head 31 and the coiled. spring 32, between the nut and the chest 24. It is obvious that many other arrangements will occur to those skilled in the art, and therefore I am not to be limited to these details. provided with passages 33, and 33 therein so arranged that when turned to one posi tion, such as shown in Figs. 7 and 8, the inlet port opening 25, is in communication through the valve passage 33 to the passage 23 or duct to allow pressure medium to flow to the left hand side of the piston head 15, and at the same time opening communica tion between the duct or passage 24 with the outlet or exhaust orifice 28. It will be understood, as hereinbefore explained, that thereupon the feed cylinder 6 is caused to move to the left until it reaches the position shown in Fig. 1, the limit of its forward travel. By raising the valve control handle 30 to its vertical position, the exhaust port 28 and inlet port 25, and the respective ports 26, 27, of the ducts or passages 23, 24 are all closed. When the control handle 30 is thrown to the opposite position, such as shown in Fig. 9, the passage 33, of the valve then opens communication between passages or ducts 25 and 27, and the exhaust port 28, is put in communication with duct 23, thereby causing the feed cylinder to travel to the right from the position shown in Fig. 1, toward the position shown in Fig. 2.

It will be observed that I have provided a pneumatic or fluid pressure feed mechanism that is exceedingly simple, requires little attention for the operation thereof, insures constant uniform feed, and which rapidly retracts the drilling machine to its initial position thereby saving time and energy and securing more perfect work than has heretofore been obtained in the machines of this class.

Moreover, it will be seen that by locating the ducts or passages which deliver the pres- The valve 29 is sure medium to opposite ends of the feeding cylinder outside of said cylinder, 1 am enabled to secure the full effective pressure on the piston to accomplish the forward feed of the machine and its quick retraction without unduly increasing the size thereof and by adequate pressure both for feeding and retracting. This in practice is a most valuable feature because if the effective piston area is prescribed on the one side or the other then a pressure which is sufficient to effect the retraction of the machine is inadequate to effect the hammer action or the advance of the'machine to its work, and a pressure which is satisfactory to operate the hammer and feed the machine forward is far too great to efiect the smooth easy and uniform retraction of the machine. This distinction becomes important where the same pressure supply connections are employed for the hammer action and for the feed and retraction of the machine.

As hereinbefore stated, it is among the special purposes of my present invention to obtain the pneumatic or fluid pressure for my feed apparatus, directly from the same source that operates the hammer without employing a separate connection therefor. I have shown a simple arrangement, but to which I am not to be limited or restricted, wherein I provide a port or passage 40 in the end of the valve chest 2, see Fi 4:,

and I screw or otherwise insert therein, a plug or nozzle 41 also provided with a duct or passage 42, therethrough, and adapted to be in constant communication with the passage 4:0. The valve 60, within the chest 2 is so located with respect to the supply connection 3, that whether said valve 60 is open or closed, as long as pressure is being supplied to the connection 3, the same is passing through the passage 40, 42, to the valve chest 24.

Likewise, on the valve chest 24:, I provide a suitable connection 45, and I connect the two connections a1 and 45, in any suitable or desired manner, such, for instance, as by the tubing or piping, flexible .or solid as desired, shown at 4:6.

It will be seen that I have herein provided double acting feed mechanism which is exceedingly simple and efficient.

It may be sometimes desirable to provide a lock for the drilling machine when the same is not in operation. Ishow a simple means for accomplishing this result, but to which I am not to be limited or restricted, wherein a set screw which screws through the shell or cradle 16, and bears against the movable cylinder 6. lif desired, and as shown, a pin 51 may be employed to allow ready control of the set screw 51.

Having now set forth the object and 11ature of my invention, and having shown and described in detail a structure embodying the principles thereof, what I claim as new and useful, and of my own invention, and desire to secure by Letters Patent, is,

1. In a drilling machine of the pneumatic hammer type, and in combination with a shell or support, a double acting or reversible air feed mechanism including a cylinder, a piston in said cylinder, said cylinder being provided with a valve chest, a two throw valve for said valve chest, said valve chest being secured to said cylinder and located upon the upper or top side thereof, and a trough secured to the top of said feed cylinder to provide a passage to carry the air pressure to the front and rear ends of the feed cylinder, said feed cylinder also being provided with ports or openings-at its extreme ends to admit the air pressure alternately to the opposite ends of the piston, said valve, air passages and piston working separately and independently of the pneumatic hammer whether the hammer is oper ating or idle.

2. In a drilling machine of the pneumatic hammer type, a double acting or reversible air feed mechanism including a cylinder, :1. piston for said cylinder, said cylinder being provided with a valve chest, a two throw valve for said valve chest, said valve chest being secured to said feed cylinder, a trough secured to said feed cylinder, said trough being in communication with ducts or ports in said valve chest to convey the air pressure to the opposite ends of said cylinder, said trough and valve chest being located on the exterior of said feed cylinder, and means for controlling said valve, air passages and piston separately and independently of the pneumatic hammer whether the pneumatic hammer is operating or idle.

In testimony whereof I have hereunto set my hand on this 20th day of October, A. D. 1915.

JAMES. c. n. VAUGHT.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents, Washington, D. U. 

